This project will develop and test a low-cost approach to using health information technology (HIT), aimed at improving the effectiveness and cost-effectiveness of care for chronic health conditions that are amenable to home self-monitoring, that is easy to disseminate. In contrast to many other HIT-based interventions, we will utilize commercial, off-the-shelf technology rather than custom, expensive HIT. We are using hypertension control among persons with diabetes as our test case because there is documented need for improving control of hypertension in this high-risk population and studies estimate that improving hypertension control in diabetes is more cost-effective than most other medical interventions and possibly even cost-saving in direct health care dollars. This high-value return on investment is important for encouraging adoption, expansion, and dissemination of HIT innovations. Our intervention will involve recruiting 400 persons with diabetes and uncontrolled hypertension receiving care through Fallon Clinic. Half of them will be randomly assigned to receive an automated blood pressure cuff capable of uploading readings through a computer, plus instruction on how to connect their cuffs at home or in the clinic to upload their information into a popular and free commercial personal health record (PHR) system. These blood pressure data from the PHR will be transferred automatically into Fallon Clinic's electronic health record system and will alert Fallon Clinic's existing team of diabetes care management nurses. Subjects whose blood pressure is uncontrolled will have their medication regimens intensified by these nurses according to protocols. Intervention subjects will receive regular outreach calls from the diabetes care nurses if their blood pressure remains uncontrolled or they are not periodically uploading blood pressure readings. After one year, we will compare outcomes between control and intervention subjects. Our primary outcomes will be change in mean blood pressure and proportion of subjects with controlled blood pressure. We will also measure a range of secondary outcomes including costs of the intervention, medication utilization, and a variety of patient-reported outcomes. Furthermore, we will interview and observe study subjects and care providers to gain a better understanding of factors affecting uptake and use of the intervention. We will examine continued use of the intervention after formal study participation ends and will also measure uptake of the intervention by control subjects offered delayed entry at the end of the formal study. Lastly, we will compare our study and findings to other, recent studies using HIT to improve hypertension control and develop a set of best practices and recommendations for future efforts in this area.